Logic control unit for data collecting, storing, transmitting and computing system



W. T- HAGE Sept. 3, 1963 AND COMPUTING SYSTEM Filed June 11, 1958.

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ATTO R N EY Sept. 3, 1963 w. T. HAGE LOGIC CONTROL UNIT FOR DATA COLLECTING, STORING, TRANSMITTING AND COMPUTING SYSTEM Filed June 11, 1958 unman-DEBUG DUUUUD EQE UEEDDDUDUUH DU UUDUUuuuE ESnUDDUD UUDUUDUDUunE 3 SEuDUDD DDUDDUUDuuuS ESDUDUUUUUUUUUDUDDuuE G ESuUDDUDUDflD DDUUuuuS l| EUEHDDU UUUUU DD nflnflfluung EEUUDUDDUDUDDUDUUuDE F EEEUDDUUUD DD .UDDDDnuE ESSBDUDDDU DD UDUDDQuS r I 2 7 Q W. T. HAGE AND COMPUTING SYSTEM 8 Sheets-Sheet 5 INVENTOR. z'Z/z'am TJ /aye BY J WW ATTOR N E Y Sept. 3, 1963 LOGIC CONTROL UNIT FOR DATA COLLECTING, STORING, TRANSMITTING Filed June 11, 1958 3 4 w 0 4 B 5 w w w 1 1 S S S S O 4 L 1 3C M 1 2 1 2 2 4 C 1 1 B n F G 2. c c o c c= Fem w u w r YO F R B F B 2 3 1 1 1.TO 01 P o T9 Q Q Q WS OS AM S S W Q S ..|..-LS H P l F S TOQ 0 b N M r S W. T HAGE Sept. 3, 1963 LOGIC CONTROL UNIT FOR DATA COLLECTING, STORING, TRANSMITTING AND COMPUTING SYSTEM 8 Sheets-Sheet 6 Filed June 11, 1958 ZBOIW wZOCUZDm mom WEDQEQ .wDnEbO muZZeGm m0 mzorzzrwmuc INVENTOR. Mf/z'am T Hays BY ATTO R N E Y Sept. 3, 1963 w. T; HAGE 3,

LOGIC CONTROL UNIT FOR DATA COLLECTING, STORING, TRANSMITTING AND COMPUTING SYSTEM Filed June 11, 1958 8 Sheets-Sheet 7 PERPoRAToR' SPIECIAL 4 MATRIX E a w of; a; 2% U.

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I'D O 0 g L E 8 b INVENTOR. m/Zz'am Tflaye BY ATTORNEY Sept. 3, 1963 w. T. HAGE 3,103,001

LOGIC CONTROL UNIT FOR DATA COLLECTING, STORING, TRANSMITTING AND COMPUTING SYSTEM Filed June 11, 1958 8 Sheets-Sheet 8 T T U T HBONEI'IOBS INVENTOR. MZ/iam Tfi age- BY ATTOR NEY m mz wmmmmm l1 [l4 aaonanoas ni d e 1Wt This inventionrelatesto logging or data transmission 7 systems and, more particularly, to a;novel control unit for suchsystems operable .to effect progressive reading, in a predetermined. sequence, of. a" pluralitypf variable magnitudes arranged in groups and to effect conversion of theindividualmagnitudes into coded magnitudes corresponding to numerical values individual magnitude.

UNITFOR DATA COLLECTING,

representative of each Testing operations under constantly changing conditions, and requiring the taking of a plurality of readings at separate stations during a test,'require personnel sufiicient in number to assure all readings being taken at substantially the same time. Otherwise, thechanging conditions over a period of time invalidate at least the earlier readings. The number of personnelrequired approaches the figure of one person for each station to be fread out.

A typical example of such an operation is'the testing of a relatively largesteam generator to determine the perice the sensing element connected to second switch, steps the second switch to its second position, and proceeds in' a like manner to' interrogate the sensing elements connected to the first positions of the succeeding switches. The same. procedure is then repeated to read out, in succession, the sensing elements connected to the second positions of the switches, with each switch being stepped, in succession, to the third position, after reading out of its second position. The operation conjtinues until all the positions'of all the analog iniits' have been read out, at which time the operation may be] terminated, or it may be cyclically repeatedasmany timesas necessary or desirable in accordance'.with test conditions. I I

'ln'interrogating each position of an analog unit, the

logic and control unit applies the analog output potential to an analog-to-digital convertor, or digitizer, which converts the measured analog output. potential to anumerical representation by means of a counter including relay banks foreach decimal placein the numerical representation. For example, if a four digit number. isyutilized, the counter will have four banks often rela'yj's each. u q

:The' logic control unit commits the digitizer output to amemory unit, thus releasingxthe digitizer for use in reading out the next data point, and then converts the c memorized digitizer output into, a punched card or tape formancethereof with, respect to such factors as steam flow, attemperation, 'feedwater heatery bleeds, heat absorptions, exit gas temperature, overall efiiciency, etc.

This testing is effected by measuring temperatures, pressures,'i flow rates and drafts at numerous stations or'loca tions, and analyzing flue gas at plural locations across the path of flow of the flue gas. The temperatures are.

measured by means of thermocouples, thepressures and flow rates are measured by suitable diaphragm devices which may convert the values into electric potentials, and the gas'analy'sis is performedby suitable analyzers which may convert the analyses to electric potentials; A complete performance test of a large steam generator by present methods may require the services of sevenmen for about one week. Since five or six of these men aretnginee'rs' normally assigned to duties other than testing,the'. making of such a test results in considerable disruption"to normal engineering activities.

In accordance with the present invention, a novel and controlgunitis provided operable to sequentially and cyclically read or interrogate each ofa plurality of sensing units, such as thermocouples'pressure voltage 1 .code such as, for example, a teletype or computer. tape code. In additiomthe logic control unit also supplies special information to the data tape .or card and energizes the tape. or card punching magnets at the'proper time. I j

The coded tape may be fed to an electronic computer which utilizes the input information to compute, for example, the heat absorptions, losses, and efiiciencyofa vapor generator. If the computer is at a reinotelocation, the coded tape may be used to operate a teletypewriter rwhich transmits the information over telephone or telefgraph wires to such remote location where the "receiving teletypewriter information is converted into a computer" "tape code. The computer output may be transmitted in a similar manner back to the test location, L For an understanding of the invention p'rinciplesreferen'ce is made to the following descriptionof atypical em'-.

logic transducers, and electrically indicating gas analyzers, and v to convert the read electrical potentials of the sensing units into jcoded characters, such as punch .marksin a card or tape, corresponding to numerical values repre sentative of the respective readings of finterrogationsl Preferably the several sensing elementsjat any test 10'- cation or at physically adjacent test locations are grouped so thatther'e areseveral groups of sensing elements. The output'leads of the sensing elements of eachgroup are connected to respective fixed contactsof a stepping switch, or similar device,whereby the grouped sensing elements may be interrogated step by step. Each stepping switch is a component part of a data-to-analog convertor or analog unit, and each analog unit includes automatically operated slide wire means for balancing the potential 'of 'each sensing element andproviding an analog unit output potential corresponding to by each sensing element. c

' In operation, the control unit initially steps the switches to the first position,finterr'ogates the sensing element connected to the first position of thefirst switch, steps the first switch to itssecondposition, interrogates the data value registered FIG. 1 is a schematic blockdiagram of a logging and tape perforating system incorporating thelogic. and con- I bqdiment thereof as'illustrated the accompanying draw- In the drawing:

trol 'unit of the invention; v r r p FI S. Z'and 3 re side and end'elevation views, resp'eotively, of a multiple stepping switch which "may be used withthe logic and controlhnit ofthefi ivention,

and incorporated in an analog unit for converting meas ured magnitudes into output potentials; j I c FIG. 4 is a schematic wiring diagram illustratingthe 1 potential balancing means of the analog unit;

FIG. 5. is a schematic wiring diagram of the digitizer and a retransmission circuit connected. to an analog unit;

FIG. 6 is a partial schematic wiring 'diagramf oftlie connection of the digitizer'to thennemo'ry, unit 10f the logic and control unit;

FIG. 7 is a schematic wiring diagram enlarging FIG. 6-; H FIG; 8 is a schematic wiring diagram'off the sc'anner of the logic and control unit;

FIG. 9' is a table of the functions performed by the logic and control unit; a

FIG. 10 is a schematicv wiring diagram ofthe, scanner,

special matrix, memory unit, and-perforato'r, illustrating two of the five logic relays; and

FIG. 11 is a schematic wiring diagram'of the system shownin block form in FIG. Lon-1y the minimum num- 3,103,001- Patented, Sept. 3, 1.9.63

the first position of the i selec .eputFpo-te QtiaIsof a plurality of analog units 10*, fwhich v I (4') Resets; the digitizer;-

1 "(5) Connects the memory mechanism to produce the numerical representations. (26 Re-loads the memorymeans with the new informa v .b'er "er. identicalor similar ly apply, in a predetermined sequence, the outpeeve: measured variable magnitudes into correspondingly varied output potentials, to the input of an analog:-

' "to-digitalQconventor, or digitizer '25 which converts]: such'outputpotentials into" stored numerical values." {The flogiefan control unit 100 controls the transfer ofth e erical values to mechanism, such as atape whichconver-ts the information'from'the 1 stepefthe' analog'units 10 m a predetermined se- (2)'rsequentially"applies the output potential of. each analog unit to digitizer 25.

- (3),"Transfers"the stored information from the digitizer -tothe memoryimeans.

' tionstored in the digitizer.

.('Z)'7F6'6C1S. special information to the converting mechanism. i

.point analog units may have their first points read and converted intofnumericah representations inse- -,quence, and after each reading er an analog unit 10, such analog unit'is stepped. to its second point for balancing f its,.Jontput potential against a'potential representative, of the magnitudegof such output potential. 'After all the I first points. have been readpthe second points of the analoggunits 10, are read in sequence with each analog b'ein:g stepped to its third point, after reading of its second point, to obtain a inew'output potential, with thissequence being repeated until 'allthe data points of all theanalog'unitshave been read.

e In storing information on a,tape,.sueh as theteletype tape/45 01" a computer tape, several conventions must be fupper-"case";code.- Consequently, each set of numerical means into the converting {Thelogic and control-unit 100 thus operatesas the.

, brain of the system whereby a plurality of multiplecomponents; sufficient to illusp 'trate thelope'ration'o'f the invention'being illustrated.

Referring: to FIGS. 1 and 1 1,. the control and logic unit lfitlro f the invention is illustrated as arranged to fourth channel. .These holes and the unpunched spaces are in'line transversely of the teletype tape.- The perforator 40 is a known mechanism which punches combinations of up to five holes simultaneously in one row transversely of tape 45.

Whilenotlimited to use therewith, the invention system i has beentested in. conjunction with a Datatron digital computer. 'Thisc'om'puter is designed touse a word of eleven charactersjconsisting of ten digits .preceded by a si-gn. As will be described more fully hereinafter, each piece ofdat-a information, punched into the tape 45, for

example, contains four digits so that the rest of the word? appearing on the computer tape must be filled in with zeros. H The line-feed and carriage-return characters, are ignored inf the computer tape conversion operation. In

addition, each word enteringthe computer must be preceded by a code indicating thesign (plus or minuslof the information. In view' of the aboverequirements, the invention" system, when feeding information to :a teletype system, utilizes aword composed of the'sig'n, two data values'of four digits each, two zjeros,"?a carriage-return code, and a iine feed 'codearranged in the follc vwingse- 'quence:

Position:

1' Sign (zero=pl-1'1s; one.'=n'1inus).- 2, 3, 4, 5- Fourdigit datum, 4 6, 7 Zeros. 8, 9, .10, 11 Four digit datum; 12 Carriage return'(CR).

' 13;. Line feed (L'F),

Each separate group of data, whether it' be a single traverse or scan? of all data points or several repeated "scan s.rnust be preceded by a code word which cornmands the computer to start entering into its storage section the information contained ,on. the following portion of the tape. 7 v V by a coded wo'rd? which commands the computerto obtain its instructions from another source. Usually the new source commands the computer to stopentering-the information into its memory or storagefsection. The p 1 -word preceding the data group iscalled, the.

p e I input order? and takes the following form: 400000OO'100CiRL'F Y r The number 4 tells the computer to make preparations for receiving tape-stored information, the fifth and sixth zeros tell thecomputer to start entering data into its storage or observedq 'llie data 'stor'ed .in the perforated tape 45 uses the 'digits -Zero throughnine. Theteletype system i v ffoi; example, 1 is constructed to print only letters unless the informationfed'to the' transmitter is preceded by an of control word and has the following form;

memory section, and the 1-00 indicates that the first data information is to be entered into the memory, cell 100.

Y The fiwor following a data groupis called the change GUOUOOZOTOOCRLF r e I e he "56 tellsthecomputer'to stop the inputdevice which,

1 with the particular computer mentioned above, isaphotodataperforatedinto a teletype tape, such as 45, must be I precededby such ,upper case code as its first-character.

' l 'iurtherniore the ite-letype equipment contains means 'direct conversion of teletype code tonumerical data on-ia'printed page. This necessitates that, the information punched onthe tape contain carriage return and line feed instructions to 'the automatic teletype printer; In the invention system, each word perforated on tape 45, C011,-

sistingof an'algebraicsign plus ten digits, is followed by l acoded line-feed and a' carriage return signal; The teletype code/representing charactersis in the form of holes punched in a tape. The standard teletype code uses five 1 longitudinally extending parallel spaced channels, and J eachwchai zictetis represented by a unique combination 5 ofv holes andunpunched spaces in the respective channels'. (For instanceythe. digit one is represented by holes in the first, second,a.;third and fifth channels of the tapfe, ,with there being an unpunched space in the reader which converts holes in the computer tape to com v-puter memory input signals.

The 20tells the computer to stop takhig-its commands from the tape andto take its commands from address 700" in its memory. A .stop commandjs usually existing at the 7700 address. Each data group ispreceded by a word called the preliminary data which gives, 'in a particular example, the number of the data group, the month, day and time. Beforex explainin-g the operation" of the system as. a

whole, it will be helpful to describe the construction and operation of individual units which are under the'contr'ol of'the control and logic unit 100. Referring to FIGS. 2 and 3, each of the analog units Iii includes a stepping switchv 11 whicnin the illustrated example, may have ten (10 contacts at each of several levels, for example,

twenty-five levels. .uI-n exemplary vapor generator performance analyses in which the invention system has been tested, each analog unit 10 is used to measure; twenty (20) data sensing: points individually ,and in sequence. The

Also, each group of data must be followed stepping switch 11 includm rotatable contact arms 12 which are stepped by a pawl l=3foperated by a magnetic coil 14. Electric conductors connect the data, sensing points, such as thermocouples'lS, to the stationary con-1 4and11.

Referring to FIG. 4, each analog unit includes means for producing a voltage equal and opposite to the data signal voltage V from the sensing element, such as thermocouple '15. This means comprises .a source of potential connected across a variable resistance having a contact operated by a motor which is controlled by an error detector sensing the difference between the voltage drop across the variable resistance and the signal voltage. -As the sensing elements, particularlythermocouples, sense temperatures varying over a relatively narrow range, the balancing arrangement includes not only the variable resistance, or slide wire, 16 but also a range resistance 17 and a suppression resistance 18. The voltage is supplied from a suitable D.C. source, such as a battery 21, whose terminals are connected across the resistances 17, '16 and 1 8 connected in series. A pointer or slide 22 operated by a motor 20 varies the value of the variable resistance 16. The direction and amount of operation of motor 20 in balancing the signal voltage is controlled by an error detector 23 'which senses any differences between the value of the balancing voltage, as measured by pointer 22 with respect to its position along resistance '16, and the signal voltage from the thermocouple 15.

Connection of the slidelwire resistance directly across the reference voltage is impractical .as an effective-refer Y ence voltage, only of the total lengthof resistance 16 would be used to cover thevtemperature rangel To accommodate narrow temperature ranges and at the same time to make use of the full length of the slide wireresistance 1-6, the range'and suppression resistances 17 a'nd'lS are added as shown in FIG. 4. If, for example, range resistance -17 has a value of 19,540 ohms, slide wire '16 has avalue of 100 ohms, and suppression resistance '18 has a value of 360* ohms then pointer 22, at the lower end of slide wire 16, sees a voltage of 18 millivolts representing about 800 F. -At' the upper end of slide wire 16, pointer 22 sees 23 millivolts or 1000 F., and the full length of the slide wire 16 is used for the 200 degree range.

The several sensing elements connectedgto any one analog unit 10 may require difiterent range suppression values. ferent values are switched into the circuit, at each data point of the analog unit by means of the selector or stepping switch 11 of the analog unit. In operation, when any particular thermocouple is cut inby operation of switch 11, the error detector 23 measures the difference between the output voltage of the thermocouple 15 and the reading indicated by slide 22 on slide wire 16. The error detector 23 then causes motor 20 to operate pointer 22 in a direction to balance the slide wire voltage against the thermocouple voltage. This action will be referred to hereinafter as the potential balancing action of the ana- Hence, range and suppression resistances of dif-- I adjusted therealongin coordination with the adjustment of pointer 22 along slide wire 16.

I The'lower end of the series of resistances26, 27 and 28 represents zero, and the upper end represents 9999*. Therefore, the position of pointer 24- along slide wire 26 will represent a percent of the total voltage across the whole circuit. Because the digitizer 25 reads out in a number containing four digits (or four decades) the numlatter is programmed to insert the decimal pointat the proper location. Because the percent voltage from slide wire '26 is an electrical value equal to the data value as measured by thermocouple 15, it may be stated that the input voltage todigitizer 25 is an analog of the data; and that digitizer 25 is thus a true analog'converter. It is the functionwof digitizer 25 to convert the output of the re-transmission circuit-to a numerical value which can be used to provide the final numerical representation. Referring to FIG. 5, the digitizer 25 includes a ramp generator- 35 which, on signal, produces a voltage which accurately increases at a constant rate with time from a small negative value to a voltage equal to the maximum voltage of power supply 29. The slide wire voltage V is shown intersecting the ramp voltage at V and the power supplyzero voltage is shown intersecting the rampat V In operation, a'rese signal brings the ramp voltage to pointA, which has a small negative voltage. The ramp voltage then begins to rise. When this voltage reaches the zero line, a'zero diiference d etector 37 starts oscillator '36. which feeds million-a-second pulses into a counter 30 which counts each pulse. When the ramp voltage has reached the value V another zeno-difierence detector 38, which is arranged to sense the difference between the ramp and slide contact voltages, stops oscillator 36. The system is so designed that it requires 9999 counts for the ramp to reach the maximum value of the voltage of power sup- -ply 29.. Therefore, the number of counts stored in the output relays 31-34 of counter-30 is a number which gives the percent of the power. supply voltage atthe position of slide wire 24 alongvoltage ramp 35.- The counterrelays are arranged in four rows of ten relays each, the respective nows measuring units, tens, hundreds, and thousands. The counter 30 thus provides a decimal readout in four digits which is used to energize one relay 31-34 in each of the four rows of ten. 1

Referring to FIGS. 6-8, 10 and 11, the control and logic unit includes an electrical memory 50 comprising relay groups 51, 52, 53 and 54 which are in decades and memorize respectively thousands, hundreds, tens and ones. The unit 100 also includes analog selector switch means 55 which may be, for example, one or more multipoint selector or stepping switches similar to the selector or stepping switch 11 of FIGS. 2 and-3.. .The principal control component of the control and logic'unit 100 is a scanner or sequencer 80. Essentially, the unit 100, including the mentioned components thereof, comprises a variety of circuits all of which are composed of two functional components, namely diodes and relays.

As is known to those skilled in the art, a memory in electrical terms contains devices, such as relays, which will store inforniation'until this information is used to perform its function and the memory is relieved of its contents, or,dumped. The four memory units 51-54 accept decimal information from the four decades 31-64 of the digitizer, and store this information so as to release the digitizer to accept information from the succeeding data point. Thereby, the information from one action of the digitizer can be read-out from the memory units into perforator 40 and on to tape 45 while the digitizer is freed to receive the next data value. As the input to memory 50 is in decimal code whereas the information is to be stored in teletype code, a conversion matrix composed of diodes is necessary for each memoryunit.

ing a wor The input to any one memory unit 51 54 comes from .one bank 31-34 of ten relays contained in the'digitizer.

For each ,data point, only one relay of the relay bank 31, 32, 33 or 34 is energized ata time. Byway of a specific example, if it is assumed that a particular memory unit 51-54. is assigned to the most significant digit of a data word and if the data value is, fior example, 2364,

the number-2 relay of the thousands decade 31 will be energized and its contact closed. .Upon receipt by the digitizer 25 of a load memory signal, the number .2 relay'in the thousands decade'31 of the digitizer cl'oses the number 2 relay in the thousands decade 51 of the 7 memory unit through power supply 56.. This connects the 2 line of thedecimal-to-teletype diode, matrix to the powersupply57 as shown in FIG. 6. The diode matrix line 2 connects diodesin teletype channels 1, 2 and 5 to teletype channel relays 61, 62 and 65 the supply of potential to these relays being through diodes 71, 72 and 75. This energizes the relays 61, 62 and 65 3 which then latch in through their contacts Ch-1, Ch2

and Ch-S. The particular relays thus remain energized even after the 2 matrix line 59 is broken upon decnergization of the 2 relay in memory unit 51.

FIG. 7 shows one complete matrix connected ,to one digitizer output decade 31 controlling memory decade 51. The memory load, memory dump and readrelay contacts 66, 67 and 68 are shown. Assuming, as in the description of FIG. 6, that the digit 2 has been counted in digitizer 25 and is to be readout, the counter .30 will have caused the 2 contact in decade 31 of the digitizer to be closed. Hence; when memory load conbe energized from source 57 and-will close their respective contacts A1 and A2, B1 and B2,, and E1 and E2; Closure ofcontacts A1, B1 and E1 latches the relays 61, .62 and 65 so that they remain energized even contact 66 is reopened to drop the 2 relay in decade 51. s

When read contact 68 is closed, perforator magnets 1M, 2M and 5M will be energized from source 58 through closedcontacts A2, B2 and E2 to. punch the :code for 2 into tape 45. Relays '61, 62 and 65 remain energized untilv dump contact 67 is opened to breakthe hold circuits for these relays. I

Each of the thirteen bits or characters comprisis read in succession into the perforator magnets M by means of the sequencer or scanner 80 which obtains its synchronization firom perforator 40, receiving one impulse at each revolution of the perlforator drive shaft. This synchronizing pulse occurs at such "a time in the perforator cycle as to enable scanner 80 to set up a coded. bit in the perforator magnets M at the proper time to cause this code to be perforated in tape 45 at the end of thecycle.

The functions of the scanner 80 are as follows:

(1) Connect one side of the power supply in sequenceto each of thirteen lines pertainingto. the bits forming thirteenth operation, scanner 80 will step from the thirteenth to the first position and repeat its cycle until stopped by removal of its driving pulse.

Referrin to FIG. '8, itwill be noted that the scanner 7 comprises a series of relays. The Syndcontact in pertoratordd is closed once for each revolution of the perforatorshaft to energize relay SR'to shift its contact of the perforator shaft, the B and F lines are alternately energized.

Scanner 80is energized through four lines. The lines 'PSj-li andPS- are connected to opposite terminals of the powersupply and are energized at all times during the scanner operation. The B line isenergized only when relaySR is deenergized, and the F line is energized when relay SR is energized.

Each of the thirteen steps of scanner 80requires two relays, resulting in a total of twenty-six relays for the thirteen steps of the scanner. Referring to FIG. 8, the relays numbered SIF through S131 are connected through other contacts. to line 'F and thus can be picked up only whenline F is energized. The relays SIB through 81313 are connected through other contacts to the line B and thus can be energized only when relay SRis deenergized.

' A twenty-seventh relay T is the transfer relay which pro- Jvid'es recycling at the end of the thirteen steps. When the scanner 80 is in operation, the relays SIF, SIB, 52F, 82B, etc. are energized in sequence. As each relay is energized, it opens the hold circuit of the preceding re-, lay and closes a contact in the pick up circuit of the following relay.

For an understanding of the operation of the scanner, Q

it can be assumed that the perforator 40is operating and the Sync contact is being closed once each revolution of the perforator, resulting in contact SR-1 shifting between line .F and line B. If push button PB is closed,

,relay S is energized and, if switch SW is closed, relay.

S is latched in the energized position by its contact 84.

At the start of the operation, relay SR is deenergized so .(4) .Step the analog-unit data point selector to the next I Scanner 80 is essentially a ring counter, advancing through each of its thirteen steps for each synchronizing pulse received. If not stopped by external means at the signal to othercircuits that line B is connected to line PS+;,through contacts SR1 and S1, which latter is closed upon energization of relay S. At the first pulse from perforator 40, the

Sync contact closes, energizing relay SR which, through contact SR-l, disconnects line B from line PSI+ and connects the latter to line F This energizes relay SlF through the normally closed contact TR-Z of relay TR,

and relay S IF is latched in the contacts S1F1.

The Sync contact is broken almost immediately, so that relay SR is dropped, again connecting line B to line PS-l-f. At this time, contact SIB-1 is closed so that relay SIB is energized causing its contact SIB-1 to latch energized position by its the relay between lines 'PSHI and l?S-., At the same time, contact SIB-3 in the hold circuit of relay 81F opens deenergizing this relay. Contact SIB-4 closes to energize relay TR which holds itself in through contact TR-1 and, by means of normally closed contact TR-2 of the pickup circuit of relay SIF, prevents the operatron of that relay until the end of the scanner cycle.

The second pulse rmm p erforator 40 closing the Sync contacts again connects line F to line PS+. At

this time, contact SIB-2 in the circuit of relay 82F .is'

closed andthis relay is picked up, closing its holding circuit at contact S2F1 and opening the circuit of relaySlB at contact S2F-3. As the Sync contact reopens, line F is disconnected from line PS;+ andline B is connected to the latter, by the dropping of'relay 'SR. Relay 82B is now picked up through the closed contact 'S2F and holds in through contact S2B-1. Contact S2B-3 opens to drop relay 82F. 1

Each time contact SR-l connects line F to line PS+, through closing of the Sync contact to pick up relay 'SR, the next relay in the sequence is energized, closing a contact to the succeeding relays circuit and breaking the hold circuit of the preceding relay. If contact SR-l is dropped to reconnect line B to line PS+, the succeeding relay is energized and the preceding relay is deenergized. This gives rise to one step composed of two acts for each pulse of perforator 40. The stepping continues until relay 81313 is energized which opens the circuit of relay TR at contact S13B-4. Relay TR recloses the pick up circult of relay 81F at contact TR-Z so that, upon the next pulse, relay SlF can be again energized and the cycle repeated if switch SW is closed. .If this latter switch is open, with contact S13-B-2 also being opened due to energization of relay 813B, relay S is deenergized to disconnect line PS;+ from the scanner'through contacts 8-1.

I Recycling can be obtained by closing switch -SW.

.The function of scanner 80 is to connect line L, which 7 is connected to line PS+, to thirteen data lines in sequence through the respective contacts S1F-L through S13F-L closed when relays SlF through S13F are energized. The destination of the data lines is determined by the logic circuit described more fully hereinafter.

Whenrelay S6F is energized, it closes a set of contacts which steps, to its next position, the analog unit ,10 from which the preceding data information was fed to digitizer 25, and steps analog selector switch 55 to the next analog unit which is already in balance and ready to be read out to digitizer 25. When relay S9F is closed, the digitizeris reset the second time for reading out of the second data point. When relay S10F is energized, it dumps and reloads memory 50- the second time, and when relay SIZF is energized, 'it steps the analog unit 10 then connected to digitizer 2'5 and steps analog selector switch 55 to the next analog unit 10. It will be noted that the operations of digitizing, loading and unloading memory 50, and stepping of the analog units 10 and analog selector switch 55 occur twice each cycle, thus providing the two data values or words which are read out in each cycle.

The destinations or routing of eleven of the thirteen readout lines sequentially energized by scanner 80 are controlled by selectively 'energizable logic relays, which are simply multiple control relays. In an analysis of the operation and performance of a steam generator, for example, five of these relays are used, and are respectively designated the preliminary data, input order, change control, data, and oxygen analysis relays. The table in FIG. 9 gives the routings or destinations for each of these relays. t

10 and the scanner 8-0 is at position 1. At this position,

current flows from the positive terminal of source 58 through the top contact of relay 95 to the zero of matrix 85. In the matrix, the current branches through the diodes forming the teletype code for zero and then through perfor-ator magnets (2M, 3M, 5M) to energize the magnets so that, on the first revolution of perforator 40, the zero code (2-3--5) is punched into tape 45. The current then returns to the negative terminal of source 58. Tape is advanced one space and the Sync contacts are closed and then re-opened to ad- Vance scanner 80 to position 2.

In scanner position 2, current flows through the second'contact of relay 95 to the 1000s memory decade 51 Where the number 1 has been memorized by selectively closed relays in the form of the teletype code for l. The current then flows through the closed cont-acts of these selectively energized relays to the perforator magnets (liM, 2M, 3M, 5M) to effectuate the punching of the 1 code (12- 3-5) into tape 45.

When scanner '80 is stepped to position 3, current flows through the third contact of relay 95 to the 100s decade 52, where the number 7 has been memorized, and thence to the perforator magnets (1M, 2M, 3M) to effect the punching of the 7 code (12--3) into tape 45. At scanner position 3, a second line is energized'to ef fect re-setting of digitizer 25, activating the digitizer to read and digitize the data from the analog unit to which the digitizer is now connected by selector switch 55.

At scanner position 4, current flows through lOs memory decade 53 to energize the pertorator magnets (2M,

4M) to punch into tape 45 the teletype code (24) for .4, which is the numeral memorized by decade 53. Similarly, at scanner position 5, current flows through the 1s decade 54 of the memory to energize the perforator magnets to punch the 2 code (1-2'-5) into tape 45. This completes the first data value, and 1742 has been punched into tape 45.

When scanner relay 85B is energized, power is supplied to a line which effects opening of dump contact 67 and load contact 66 (-FIG. 7), to result in the relays of memory dumping the data value 1742 and memorizing the new data value digitized when digitizer 25 was reset at scanner position 3.

At scanner positions 6 and 7, the current flows through the zero section of matrix 85 so that 0 is punched into tape 45 at each of these positions. In addition, a second line is energized at scanner position 6 to step selector switch 55 from the analog unit 10, digitized by resetting of the digitizer 25 at scanner position 3 and memorized by memory 50 when scanner relay 85B Was energized, to the next analog unit 10. This action automatically steps the just vacated analog unit 10 to its next data point.

At scanner positions 8, 9, 10 land 11, the number which was loaded into memory 50 immediately after dumping of number .1742 is punched into tape 45 in the manner :The several relays are selectively energized, one at a time, by means of appropriate control switches on the control console of FIG. 1. The preliminary data relay is connected'to special matrix 85 and also to presettable switches on the control' console for setting the test number, month, day, hour, and minute of the test. The input order and change control relays are connected to special matrix :85. .The data and oxygen analysis relays are connected to matrix 85 and also to memory unit 50*. j

Referring to FIG. 10, the action of scanner 80 while data relay 95 and change control relay 90 are successively energized be described. Assuming that data re1ay 95 is energized and that data from an analog unit 10 (in thefonm of a value 1742, for example) has been loaded into memory 50, theflanalog selector switch 55 has stepped to the next analog unit 10',

described in connection with scanner positions 2, 3, 4 and 5. In addition, the digitizer is reset at scanner position 9, as described for scanner position 3, and memory 50 is dumped and re-loaded at scanner position 111, as

described for scanner position 5 upon energization of relay SSB. At scanner position 12, the selector switches 55 and 11 are stepped as at scanner position 6, while current is supplied to perforator 40 through the line feed sectionof special matrix 85. At scanner position 13, pertor-ator 40 is energized through the carriage return section of special matrix 85, completing reading of the word into tape 45.

As. each stepping switch 11 and 55 is stepped inde pendently, means are provided for assuring, that each switch is at its presupposed position at any time during the data taking operation. This is effected by providing contacts on the stepping switch 11 of each analog unit 10 and a contact on the analog selector switch 55 so that a to position 1.

data relay 95.

I Sync contact is madeiat the zero and twenty positions illustrated, serve to assure all the analog stepping switches and the analog selector switch 55 being homed to zero at the start of eachjdata run, and that all the analog stepping switches 11 reach the position 20 at the end of the data run. This feature thus assures that each switch has stepped at the proper time during the data run;

'It all analog stepping switches 11 and the analog selector switch 55 are not at zero after the homing action, the system will stop at that point in the cycle and data will not be taken. If, at the end of any one data taking cycle, all analog stepping switches are not in the position 20, an out of Sync light be lit and repetition of the data; taking cycle .will not proceed automatically.

The logic and control unit 100 also provides for a visual display of the data point being interrogated and the numerical value of the data, which provides a means of checking the system when it is in operation. The data point indication is obtained from two levels of the step ping switch 11 in each analog unit by means of a matrix, in the analog unit, which converts the position or level number to binary coded decimal notation. The

analog positions, for example from v1 to 20, are resolved into configurations of six wires (not shown) coming irom each analog unit '10. At the logic control unit end Y. of these wires, the signals are re-converted to decimal code by means of a relay matrixan-d caused to light the scribed.

Visualindication of the 'data'value is obtained directly [from the digitizer readout relays in the memory units 51- '54, contacts of these relays lighting appropriately nurnbered lights in indicator 102 (FIG; 1) to provide the data value indication.

The logic and control unit is also provided with push button selector switches, on-ofi switches and indicating lights, which have not been illustrated, to enable complete operation of the system from ia'single control console such as shown at 103 in FIG. 1. By pushing a preliminary data button, the preliminary data relay is energized, which results in reading into tape 45 of an upper case code, a zero, then ten information bits, as set on the ten preliminary data selector switches mounted in the control console, and finally the linedeed and carriage-return code. When the ata button is pushed,

- all stepping switches 11 and 55 are moved to the zero position and, if synchronized, are stepped successively This is efiected by enengization of the After four seconds delay for the first analog unit :10 to balance, the scanner 8'0 makes one 'dry? .run to load memory 50. On the next cycle of scanner 80, all the data will beread into tape 45 on a.

continuous basis. 1 1 g -A single-cycle-repeat-cycle switch is provided which, if on ,single-cycle, will result in the data taking action ceasing after-the last data point has been punched into tape 45.- In the repeat-cycle position, the complete data cycle will be repeated-until stopped, providing synchronization is indicated'at' the zeroand last (suchas twentieth)" positions of the analog stepping switches 11. By

pressing a data stop button, the data taking cycle may connected to the digitizer. The digitizer resetcontrol pertmits reading .out of the data into visual indicator 102. Y

Perforator 40 cannot be operated on single data values and can be brought into operation only during the automatic readout operation.

"Ilhe procedure in obtaining-of oxygen analysis data, as a during testing of a steam generator, diilers because of the fiact that the data points cannot be interrogated in rapid analysis" relay is enengized. At the end orfeach data:

reading, the one-minute timer is recycled and the action is repeated. 5 v i For summarizing the preceding description, reference is made to FIG. 11 to illustrate the action of the system as it obtains temperature data trom three thermocouples and converts these values to teletype code perforated on five channel tape.

The last' half of the previous cycle of scanner-180' has just reset digitizer 25, at scanner position'9, loaded meme cry 50 with the data from position 5 of analog unit 3,

shown and described in detail to illustrate the application.

stepped stepping switch .111 of analog unit 3 to position 6,

and stepped analog selector switch 55 to analog unit 4.

' Scanner 8d is now in position 1, and data logic relay 95 is energized. Perforator 40, through the Sync? contact, is causing scanner :to step through its thirteen positions which perform the following points numbered below;

(5) The ls decade 54 is read into tape 45, and memor 50 is dumped and reloaded from digitizer 25. T (6) A zero is read into tape 45 and analog selector switch 55 is stepped to analog unit 5, while at'tlie same time,

analog unit 4 is stepped to its positionjd. (7) A zero is read into tape 45. V (8) The 1000s decade 51 holding the first digit of analog unit 4, position 5, is read'into tape 45.

( 9) 'llhelOOs decade 52 is read into tape 45 and digitizer 25 is reset to digitize'thedatatrom analog unit 5, position or level 5 (10) The '10s decade 53 is read into tape 45.

(1.1) The 1s decade 54 is read into tape 45, and memory 50 is dumped and reloaded from digitizer 2 5 with the information "from position 5 of analog unit 5.

(12.) A carriagereturn code is punched into tape 45, analog selector55 is stepped to analog unit 6 (not or level 6. v

(13) A line feed code is perforated into tape 45.

shown),*a'nd analog unit 5 is stepped to-its position The system will continue to read out the fi-fth position orlevel of each analog unit \10 and step each analog unit to its sixth positionor level, thus allowing the maxiunits 10 have been read at the sixth position or level, they are again read in sequence atthe seventh posit-ion or level, and so forth until all of the positions andlevels of each of the analog units have been read.

While a specific embodiment of the inventionhas been functions at each of the of the invention principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1, In an apparatus for converting analog signals into corresponding digital representations, in combination, a plurality of selector switches each having a plurality of positions, circuitry for connecting each of said positions to a separate analog signal source, a digitizer for converting said analog signals into cor-responding digital representations, a source of electric potential, cyclically operable control means energized by said source connecting each of said selector switches to said digitizer one after another, and including means advancing each selector switch one position immediately after the digitizer 2. Apparatus as claimed in claim 1 wherein the analog signals are electrical potentials.

3. In an apparatus for converting analog signals into corresponding digital representations, in combination, a plurality of selector switches each having a plurality of positions, each position connected to a variable source of electric potential, a digitizer for converting the electric potentials into corresponding digital representations, a source of electric potential, cyclically operable control means energized by said source connecting each of said selector switches to said digitizer one afite-r another for a predetermined increment of time and including means maintaining each selector switch stationary while the digitizer is connected thereto and advancing each selector switch one position immediately atter the digitizer is disconnected therefrom and' connected to the succeeding selector switch. I

4. In a data logger tor periodically logging in digit form the values ot a plurality of physical quantities, in combination, a plurality of transducers arranged in groups, each transducer arranged to produce an electric signal corresponding in magnitude to the value of a separate one out the physical quantities, a selector switch having a plurality of positions for each of said groups oftransmitters, circuitry for connecting each of the transducers in a group to a separate position of the associated selector switch, a digitizer for converting electrical potentials int-o corresponding digital representations, a source of electric potential, cyclically operable control means energized by said source successively connecting each of the selector switches to said digitizer tor a predetermined 14 increment of time, and including means maintaining a selector switch stationary while the digitizer is connected thereto and advancing the selector switch one position upon the digitizer being disconnected therefrom and connected to the succeeding selector switch.

5. Apparatus for continuously scanning a plurality of groups of electrical quantities, comprising in combination, an analog unit associated with each of said groups having a multiple-position selector switch and a null balance potentiometer connected thereto, circuitry for connecting each electrical quantity in any one group to an individual position of the selector switch in the analog unit associated with the group, a retransmitting slidewire operated by each of thenull halance otentiometers for producing a potential corresponding to the magnitude of the electrical quantity then connected thereto through the selector switch, a digitizer for converting electrical potentials into corresponding digital representations, means for successively connecting each of the analog units to said digitizer for a predetermined increment of time and cyclically operable control means maintaining each selector switch stationary while the digitizer is connected thereto and including means advancing each selector switch one position upon the digitizer being disconnected therefrom and connected to the succeeding selector switch whereby the null balance potentiometer is substantially balanced during thetime the analog unit is disconnected from the digitizer.

References Cited in the file of this patent UNITED STATES PATENTS 2,401,621 Desch June 4, 1946 2,504,931 Knudsen Apr. 18, 1950 2,655,625 Burton Oct. 13, 1953 2,656,524 Gridley Oct. 20, 1953 2,680,240 Greenfield June 1, 1954 2,736,006 Langevin Feb. 21, 1956 2,759,784 Burke Aug. 21, 1956 2,775,754 Sink Dec. 25, 1956 2,787,418 MacKnight Apr. 2, 1957 2,828,482 Schumann Mar. 25, 1958 2,835,884 Markow May 20, 1958 2,839,737 Dalglish June 17, 1958. 2,872,670 Dickinson Feb. 3, 1959 2,875,427 Koppel Feb. 24, 1959 2,908,894 Kienast Oct. 13, 1959 2,981,107 Anderson Apr. 25, 1961 

1. IN AN APPARATUS FOR CONVERTING ANALOG SIGNALS INTO CORRESPONDING DIGITAL REPRESENTATIONS, IN COMBINATION, A PLURALITY OF SELECTOR SWITCHES EACH HAVING A PLURALITY OF POSITIONS, CIRCUITRY FOR CONNECTING EACH OF SAID POSITIONS TO A SEPARATE ANALOG SIGNAL SOURCE, A DIGITIZER FOR CONVERTING SAID ANALOG SIGNALS INTO CORRESPONDING DIGITAL REPRESENTATIONS, A SOURCE OF ELECTRIC POTENTIAL, CYCLICALLY OPERABLE CONTROL MEANS ENERGIZED BY SAID SOURCE CONNECTING EACH OF SAID SELECTOR SWITCHES TO SAID DIGITIZER ONE AFTER ANOTHER, AND INCLUDING MEANS ADVANCING EACH SELECTOR SWITCH ONE POSITION IMMEDIATELY AFTER THE DIGITIZER IS DISCONNECTED THEREFROM AND CONNECTED TO THE SUCCEEDING SELECTOR SWITCH. 